Two public data points, added together:
- $2,337 — average gross profit per used-vehicle unit, per NADA (National Automobile Dealers Association). New-car gross runs lower, but invoice / holdback / end-of-quarter incentive gaps create comparable buyer-side overpayment.
- Asking-vs-fair spread — most dealer listings run several hundred to a few thousand dollars above fair market value before negotiation.
Combined, unprepared buyers face $3,000+ at stake on a typical deal.
Academic floor: Indiana, Cornell, and Leuphana University research pegs a rigorously measured minimum of $1,117 in buyer overpayment just from not knowing the market — before any negotiation even begins.